UK, Canada, and EU CPI data will be added in a future update. Currently US CPI-U data (1913–2024).
Equivalent Value
$—
Enter an amount and select years above
Cumulative Inflation
—%
Avg Annual Rate
—%
Purchasing Power
—¢/dollar
Purchasing Power Decay
Real value of original amount over time (inflation-adjusted)
| Year | CPI | Equivalent Value | Purchasing Power |
|---|
Inflation Breakdown by Decade
| Period | Inflation | Avg Annual Rate | $100 became |
|---|
How US Inflation Works
Inflation is the sustained rise in the general price level of goods and services over time. The US Bureau of Labor Statistics (BLS) measures it using the Consumer Price Index for All Urban Consumers (CPI-U), which tracks a "basket" of goods including food, housing, transportation, medical care, and recreation.
The Formula
Worked Example: $100 in 1980 → 2024
CPI-U in 1980: 82.4 (annual average). CPI-U in 2024: ~313.5 (annual average estimate).
- Equivalent value = $100 × (313.5 / 82.4) = $380.46
- Cumulative inflation = 280.5%
- Average annual rate = (313.5 / 82.4)^(1/44) − 1 ≈ 3.06%/year
- Purchasing power of a 1980 dollar = 82.4 / 313.5 ≈ $0.26
In practical terms, what you could buy for $100 in 1980 would cost about $380 today. This is why wage growth that doesn't keep up with CPI represents a real pay cut even if the nominal number increases.
US Inflation by Era
- 1913–1920 (WWI era): Dramatic inflation, peaking at ~17.8% in 1917. War-time demand shock and supply disruptions.
- 1920–1940 (Deflation): The Great Depression brought severe deflation — prices actually fell from 1929 to 1933.
- 1940s (WWII): Price controls during the war; post-war release drove ~14–18% inflation in 1946–1947.
- 1950s–1960s: Relatively low and stable inflation (1–4%/year). The postwar boom era.
- 1970s–early 1980s (Stagflation): Oil shocks and loose monetary policy drove inflation to 11% (1974) and 13.3% (1979). The Fed's aggressive rate hikes under Volcker broke the cycle by 1983.
- 1983–2020 (The Great Moderation): Largely stable 2–4% inflation, occasionally dipping below 1%.
- 2021–2023 (Post-pandemic): Supply chain disruptions and fiscal stimulus drove the highest inflation since the 1980s: 4.7% (2021), 8.0% (2022), 4.1% (2023).
- 2024: Inflation moderated to approximately 2.9%, approaching the Fed's 2% target.
Frequently Asked Questions
What is CPI-U?
CPI-U (Consumer Price Index for All Urban Consumers) is published monthly by the U.S. Bureau of Labor Statistics. It measures price changes for a basket of goods and services bought by urban households — approximately 93% of the US population. It is the most widely cited US inflation measure.
How do you calculate inflation between two years?
Divide the CPI of the target year by the CPI of the source year, then multiply by the original amount: Equivalent = Amount × (CPI_target ÷ CPI_source). Cumulative inflation % = (CPI_target ÷ CPI_source − 1) × 100.
What is purchasing power?
Purchasing power is the real value of money — how many goods and services a dollar can buy. Inflation erodes purchasing power: if inflation averages 3%/year, $1 today buys what $0.74 bought 10 years ago. Wages that don't keep up with CPI represent real pay cuts.
Which years had the highest US inflation?
The highest inflation years were 1917 (~17.8%, WWI), 1947 (~14.4%, post-WWII), 1979 (~11.3%, stagflation), 1980 (~13.5%, peak stagflation), and 2022 (~8.0%, post-pandemic).
What is the average US inflation rate?
The US average annual inflation rate from 1913 to 2024 is approximately 3.2%. Since 1983 (after the Volcker disinflation), the average has been closer to 2.5–3%. The Federal Reserve targets 2% long-run inflation.